29. Recombinant DNA Technology Flashcards
What is the definition of recombinant DNA?
Joining together of DNA molecules from two different species, which is inserted into a host organisms to make new genetic combinations
What are the two methods to produce transgenic plants?
Agrobacterium transformation and a DNA gun
What is the agrobacterium method of plant transformation?
Describe what agrobacterium is and how its used
Agrobacterium is a bacteria that infects plant cells causing crown gall tumours in nature, it does this by integrating a section of its T-DNA into the plants genome.
Its used as a transgene vector in vitro by removing the tumour-inducing section of T-DNA but leaving the border regions and vir genes. Then it can be transferred to the plants chromosomes and replicated as its naturally goes into the plants DNA.
The agrobacterium has the gene of interest and an antibiotic resistance gene inserted into the plasmid it so it can replicate
What is a DNA gun and how does it work?
The DNA gun shoots DNA coated pellets onto plant cells, which then the plant cells undergo gene expression to express the target gene in the plant.
How are transgenic genes inserted into animals?
Nuclear injection - Foreign DNA is inserted into the animal cells nucleus at an early stage in development. When fertilisation and cell division occur, all cells will be genetically modified and all animals will carry the gene
Why is it important to use appropriate promoters and regulatory regions with transgenes?
Promoters and regulatory regions are the reason why the gene is expressed.
There must be an regulatory region specific to the gene needed changing (eg leaf specific to change the leaf).
The gene promoter must be specific to the type of cell (eukaryotic vs prokaryotic) due to a eukaryotic gene is only able to be transcribed in a eukaryotes organism.
The coding region can be bacterial because translation had a universal genetic code
How does PCR determine if an organism is transgenic?
By displaying the test - DNA from transgenic organism
Displaying three controls - DNA from non transgenic animal, transgene DNA and no DNA
In the PCR, the DNA from the transgenic organism will be shown along with transgene DNA
What is the difference in extrinsic and intrinsic concerns with GMOS?
Extrinsic - scientific concerns that can be tested (environmental effects)
Intrinsic - moral/ethical concerns, cant be tested
